Study On The Metallogenesis And Mineralogy Characteristics Of Jinchangyu Gold Deposit, Jidong Area

The Jinchangyu gold deposit is located in the east part of the Malanyu anticlineand the west part of the Shahaiguan uplift, where metamorphic rock units, faults, andfolds were well developed. On the basis of field geological survey, observations fromhand specimens and microscope, this study distinguished four metallogenic stages forthe Jingchangyu deposit, which are: albite-quartz stage, quartz-sulfide stage, whitequartz vein stage, and quartz-carbonate stage.The metallic mineral in Jinchangyu deposit is pyrite, chalcopyrite, galena andsphalerite, and gold and the gangue mineral is quartz, albite, chlorite, sericite andcarbonate (dolomite). Use the EPMA analyse those minerals. The pyrite andchalcopyrite in the deposit are depleted in S, showing a signature of hydrothermalorigin. The galena in the deposit has lower Pb content, and the sphalerite ischaracterized by high Fe content, displaying high temperature hydrothermal affinity.In the granule of gold, form core to edge, the Au content decreasing with increase Ag.The fineness of gold in the deposit is generally high.The H-O-S isotopic analysis indicates that the ore-forming fluid in theJinchangyu gold deposit may derive from mantle magma.On the basis of the trace element compositons of pyrite, sphalerite, and chlorite,the gold fineness, and the homogenization temperature of fluid inclusions, thetemperature is medium-high.According the research above, the Jinchangyu gold deposit is a mediumtemperature hydrothermal deposit, which mainly resulted from magmatichydrothermal process.